[Clinicopathological study of colorectal cancer in young adults including a case of cancer family syndrome].

During the last 6 years, we examined 402 cases (including 5 cases in their 20's and 17 cases in their 30's) of colorectal cancer. We compared three groups (cases in their 20's, cases in their 30's, and cases over 40 years old), and had the following results. Cases in their 20's had a higher rate of familial history of colorectal cancer, and the cancer was located mainly in the proximal colon. Well differentiated and moderately differentiated adenocarcinoma was dominant in the cases in their 30's and in those over 40 years old. On the other hand mucinous adenocarcinoma and signet ring cell carcinoma was dominant in the cases in their 20's. A case of cancer family syndrome is also presented.